No network connectionSupport

Okay so I didn't pay my bill for a while and had my service cut, paid it in full so I got my service back, no issue there. Service only lasted for a day or two then I started getting the whole "your sim card does not allow a connection to this network" message. I called Virgin and they told me I need a new SIM card so I went and got one the person that sold it to me called Virgin and set it up but yea no change. Did a factory reset, nothing. Took it apart removed everything a few times and put it back again nothing. I don't have the money atm to replace it so I need some help because it's driving me crazy.